Flex circuit with single sided routing and double sided attach

ABSTRACT

A method for providing electrical connections to both sides of a touch sensor panel is disclosed. The method comprises forming conductive traces on a first surface of a base film, shaping the base film to form first and second attachment areas that include the conductive traces, forming a conductive shield over the conductive traces, wherein the shield is electrically coupled to one or more of the conductive traces, and folding the base film such that the conductive traces on the first and second attachment areas are positioned and aligned for attachment to pads on first and second sides of the touch sensor panel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.12/122,441, filed May 16, 2008, the entire disclosure of which isincorporated herein by reference.

FIELD OF THE INVENTION

This relates generally to touch sensor panels, and more particularly, tocost-effective flex circuit designs capable of being attached to bothsides of a touch sensor panel.

BACKGROUND OF THE INVENTION

Many types of input devices are presently available for performingoperations in a computing system, such as buttons or keys, mice,trackballs, joysticks, touch sensor panels, touch screens and the like.Touch screens, in particular, are becoming increasingly popular becauseof their ease and versatility of operation as well as their decliningprice. Touch screens can include a touch sensor panel, which can be aclear panel with a touch-sensitive surface, and a display device such asa liquid crystal display (LCD) that can be positioned partially or fullybehind the panel so that the touch-sensitive surface can cover at leasta portion of the viewable area of the display device. Touch screens canallow a user to perform various functions by touching the touch sensorpanel using a finger, stylus or other object at a location dictated by auser interface (UI) being displayed by the display device. In general,touch screens can recognize a touch event and the position of the touchevent on the touch sensor panel, and the computing system can theninterpret the touch event in accordance with the display appearing atthe time of the touch event, and thereafter can perform one or moreactions based on the touch event.

Mutual capacitance touch sensor panels can be formed from a matrix ofdrive and sense lines of a substantially transparent conductive materialsuch as Indium Tim Oxide (ITO), sometimes arranged in rows and columnsin horizontal and vertical directions on a substantially transparentsubstrate. In some touch sensor panel designs, ITO drive and sense linescan be formed on opposite sides of the same substrate in a configurationreferred to herein as double-sided ITO (DITO). The substantiallytransparent drive and sense lines can be routed to one edge of thesubstrate for off-board connections using conductive (e.g. metal) tracesin the border areas of the substrate where transparency is not required.However, it can be expensive to manufacture the one or more flexcircuits that are required to provide off-board connectivity for thedrive and sense lines.

SUMMARY OF THE INVENTION

This relates to a flex circuit having conductive traces formed on onlyone side of a base film for attaching to both sides of a DITO touchsensor panel. By having conductive traces formed on only one side of thebase film, the number of process steps and fabrication cost can bereduced because only a single etching step is needed. Furthermore,because the flex circuit is thinner, the resultant space savings can beutilized for other features in a device without enlarging the overalldevice package.

The flex circuit can be formed from a base film and can be bonded toboth the top and bottom sides of the touch sensor panel at one end ofthe touch sensor panel. The flex circuit can include conductive traces(e.g. copper) and an insulator formed only on the side of the flexcircuit that faces the touch sensor panel when bonded to the touchsensor panel. The flex circuit can be formed with a bend so that it canbe attached to pads formed on either side of the touch sensor panel. Atail, which can be integrally formed with the flex circuit, can extendaway from the touch sensor panel and can contain tail conductors forattaching to a main logic board.

The flex circuit can include a first attachment area that can includeactive conductors and dummy conductors formed along its length formaking electrical connections with pads on a top surface of the touchsensor panel. The flex circuit can also include a second attachment areathat can include lower conductors formed at its distal ends for makingelectrical connections with pads on a bottom surface of the touch sensorpanel. In some embodiments, lower conductors on the second attachmentarea are arranged in conjunction with active and dummy conductors on thefirst attachment area so that when the flex circuit is folded and bondedto the touch sensor panel, the lower conductors on the bottom surface ofthe touch sensor panel and the active and dummy conductors on the topsurface are not on directly opposing sides of the touch sensor panel.This arrangement can minimize unwanted coupling of signals between theconductors.

All traces and conductors on the flex circuit can be formed on the sameside of the flex circuit. Because the traces and conductors are formedon the same side of the flex circuit, no vias and plating are required,and a thinner flex circuit can be manufactured. As a result, a bend canbe formed in the flex circuit with the very small radius required by thethinness of the touch sensor panel. The thinness of the flex circuit canhave other advantages such as providing more room in the z-direction forother electronics and/or mechanical structures, or allowing for thinneroverall devices. In addition, forming only a single layer of conductorsand traces can reduce the number of process steps required (because onlya single etching step is needed), which can reduce manufacturing costs.

In the first attachment area, a particular number of dummy conductorscan be formed between the active conductors. The number of dummyconductors, and the spacing between the dummy conductors and the activeconductors, can be chosen (e.g., empirically) in accordance with thetype and thickness of the flex circuit and the cross-sectionaldimensions of the conductors. By the proper selection of conductorspacing, enough space can remain between the conductors (dummy andactive) to retain most of the ACF underneath the first attachment area,minimizing the amount of ACF that is squeezed out.

The second attachment area can include a base film (e.g. polyamide),upon which a conductive trace layer (e.g. plated copper) and aninsulator (a.k.a. coverlay or cover film) can be formed. A stiffener,which also acts as a spacer, can be attached at the distal end of thesecond attachment area to ensure that sufficient bonding pressure isachieved at the distal end.

To provide enhanced shielding for the single-sided flex circuits, thinconductive films can be attached to both sides of the flex circuits. Theflex circuit can include a base film upon which a layer of conductivetraces (e.g. copper) and an insulator can be formed. One or moreconductive traces can be held at a fixed potential (e.g. ground). In oneembodiment, a first opening (or notch) in the insulator can be formedover a particular conductive trace that is held at a fixed potentialsuch as ground. Conductive film can then be applied over the insulator,where it can conform to the shape of the opening and make electricalcontact with one or more of the fixed potential traces to hold theconductive film at the fixed potential. When the conductive film is heldat the fixed potential, it can serve as a shield for the conductivetraces.

In another embodiment, before any conductive film is applied, a secondopening (or notch) can also be formed through the base film and theinsulator, while avoiding any conductive traces. Conductive film canthen be applied over the insulator, where it can conform to the shape ofthe opening (or notch) and make electrical contact with one or more ofthe fixed potential traces to hold the conductive film at the fixedpotential. Conductive film can then be applied over the base film, whereit can conform to the hole and make electrical contact with theconductive film on the opposite side. In this manner, the conductivefilm on both sides of the flex circuit can be held at a fixed potentialand serve as shields.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a illustrates a side view of an exemplary flex circuit 100according to embodiments of the invention.

FIG. 1 b illustrates a perspective view of the exemplary flex circuit ofFIG. 1 a according to embodiments of the invention.

FIG. 1 c illustrates a side view of conductive traces formed on one sideof a flex circuit base film according to embodiments of the invention.

FIG. 2 a illustrates a top view of an exemplary first attachment area onthe flex circuit of FIG. 1 b according to embodiments of the invention.

FIG. 2 b illustrates a side view of an exemplary first attachment areaon a flex circuit having a first conductor configuration.

FIG. 2 c illustrates a side view of an exemplary first attachment areaon a flex circuit having a second conductor configuration.

FIG. 2 d illustrates a side view of an exemplary first attachment areaon a flex circuit having a third conductor configuration according toembodiments of the invention.

FIG. 3 illustrates a top and side view of a distal end of an exemplarysecond attachment area as shown in FIG. 1 b according to embodiments ofthe invention.

FIG. 4 a illustrates a side view of an exemplary flex circuit includingconductive film on the top side and optionally the bottom side accordingto embodiments of the invention.

FIG. 4 b illustrates a top view of an exemplary flex circuit with a holein an insulator for holding at least one conductive film at a fixedpotential according to embodiments of the invention.

FIG. 4 c illustrates a top view of an exemplary flex circuit with anotch in an insulator for holding at least one conductive film at afixed potential according to embodiments of the invention.

FIG. 4 d illustrates a top view of an exemplary flex circuit with adifferent notch in an insulator for holding at least one conductive filmat a fixed potential according to embodiments of the invention.

FIG. 4 e illustrates a top view of an exemplary flex circuit with nonotch, but with conductive films extending a beyond base film andconnected together for holding both conductive films at a fixedpotential according to embodiments of the invention.

FIGS. 5 a and 5 b illustrate perspective views of an exemplary flexcircuit in its original flattened fabrication configuration according toembodiments of the invention.

FIG. 6 illustrates an exemplary computing system including a touchsensor panel connected to a panel subsystem using the flex circuitaccording to embodiments of the invention

FIG. 7 a illustrates an exemplary mobile telephone having a touch sensorpanel connected to a panel subsystem using the flex circuit according toembodiments of the invention.

FIG. 7 b illustrates an exemplary digital media player having a touchsensor panel connected to a panel subsystem using the flex circuitaccording to embodiments of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following description of preferred embodiments, reference is madeto the accompanying drawings which form a part hereof, and in which itis shown by way of illustration specific embodiments in which theinvention can be practiced. It is to be understood that otherembodiments can be used and structural changes can be made withoutdeparting from the scope of the embodiments of this invention.

This relates to a flex circuit having conductive traces formed on onlyone side of a base film for attaching to both sides of a DITO touchsensor panel. By having conductive traces formed on only one side of thebase film, the number of process steps and fabrication cost can bereduced because only a single etching step is needed. Furthermore,because the flex circuit is thinner, the resultant space savings can beutilized for other features in a device without enlarging the overalldevice package.

Although embodiments of the invention may be described and illustratedherein in terms of DITO touch sensor panels, it should be understoodthat embodiments of the invention are also applicable to other touchsensor panel configurations, such as configurations in which the driveand sense lines are formed on different substrates or on the back of acover glass, and configurations in which the drive and sense lines areformed on the same side of a single substrate.

FIG. 1 a illustrates a side view of an exemplary flex circuit 100according to embodiments of the invention. Note that FIG. 1 a is not toscale, and has exaggerated dimensions, particularly in the z-direction,for purposes of illustration only. In the example of FIG. 1 a, flexcircuit 100 can be formed from base film 110 and can be bonded to boththe top and bottom sides at one end of touch sensor panel 102. Flexcircuit 100 can include conductive traces 112 (e.g. copper) andinsulator 114 formed only on the side of the flex circuit that facestouch sensor panel 102 when bonded to the touch sensor panel. In theexemplary embodiment of FIG. 1 a, flex circuit 100 can be formed withbend 106 so that it can be attached to pads 116 and 142 formed on eitherside of touch sensor panel 102. Tail 104, which can be integrally formedwith flex circuit 100, can extend away from touch sensor panel 102 andcan contain tail conductors 118 for attaching to a main logic board.

FIG. 1 b illustrates a perspective view of the exemplary flex circuit ofFIG. 1 a according to embodiments of the invention. Note that FIG. 1 bis also not to scale, and has exaggerated dimensions, particularly inthe z-direction, for purposes of illustration only. In the example ofFIG. 1 b, flex circuit 100 can include first attachment area 104 thatcan include active conductors 120 and dummy conductors 122 formed alongits length for making electrical connections with pads on a top surfaceof touch sensor panel 102. Flex circuit 100 also includes secondattachment area 106 that can include lower conductors 124 formed at itsdistal ends for making electrical connections with pads on a bottomsurface of touch sensor panel 102. In some embodiments, lower conductors124 on second attachment area 106 are arranged in conjunction withactive and dummy conductors 120 and 122 on first attachment area 104 sothat when flex circuit 100 is folded and bonded to touch sensor panel102, the lower conductors on the bottom surface of the touch sensorpanel and the active and dummy conductors on the top surface are not ondirectly opposing sides of the touch sensor panel. This arrangement canminimize unwanted coupling of signals between the conductors.

All traces 112 and conductors 118, 120, 122 and 124 on flex circuit 100can be formed on the same side of the flex circuit according toembodiments of the invention. Although FIGS. 1 a and 1 b illustrate bend106 having an exaggerated radius for purposes of illustration only, inpractice the bend can be required to have a very small radius given thethinness of touch sensor panel 100. Because the traces and conductorsare formed on the same side of flex circuit 100, no vias and plating arerequired, and a thinner flex circuit can be manufactured. As a result,bend 106 can be formed with the very small radius required by thethinness of touch sensor panel 100. In contrast, conventional flexcircuits having traces on both sides require vias through the base filmand plating to establish an electrical connection through the via.Because of the dual traces and plating, conventional flex circuits aregenerally stiffer and cannot form bends with very small radii.

The thinness of the flex circuit achieved according to embodiments ofthe invention can have other advantages such as providing more room inthe z-direction for other electronics and/or mechanical structures, orallowing for thinner overall devices. In addition, forming only a singlelayer of conductors and traces can reduce the number of process stepsrequired (because only a single etching step is needed), which canreduce manufacturing costs.

FIG. 1 c illustrates a side view of conductive traces 112 formed on oneside of base film 110 according to embodiments of the invention. Asmentioned above, in conventional flex circuits with traces on both sidesof a base film, vias are needed to make connections between layers, andtherefore plating is needed to provide conductivity through the vias.However, when plating is applied over traces 112, the traces becomethicker, necessitating wider spacing between traces to ensure thatshorts between traces do not occur. Because single-sided embodiments ofthe invention do not require plating, a finer pitch (P) between tracescan be achieved, which can result in smaller flex circuits.

FIG. 2 a illustrates a top view of an exemplary first attachment area onthe flex circuit of FIG. 1 b according to embodiments of the invention.In the example of FIG. 2 a, first attachment area 204 can be bonded downto touch sensor panel 202 with anisotropic conductive film (ACF), whichcan form a conductive bond between the conductors on the firstattachment area and the pads on the touch sensor panel. Because pressureis used to bond first attachment area 204 to touch sensor panel 202,some ACF can be squeezed out during bonding, as shown at 226. In touchscreen embodiments, where optical clarity of touch sensor panel 202 isimportant, it is desirable to minimize the amount of ACF that getssqueezed out during bonding so that it does not intrude into thesubstantially transparent areas of the touch sensor panel.

FIG. 2 b illustrates a side view of exemplary first attachment area 204on flex circuit 200 having a first conductor configuration. In theexample of FIG. 2 b, if active conductors 220 are spaced too closelytogether, there can be insufficient spaces between conductors to containACF 226, and as a result, an excessive amount of the ACF can be squeezedout into the substantially transparent areas of the touch sensor panel.

FIG. 2 c illustrates a side view of exemplary first attachment area 204on flex circuit 200 having a second conductor configuration. In theexample of FIG. 2 c, if active conductors 220 are spaced too far apart,first attachment area 204 (which can be formed from flexible base film)can be pressed down and fill in much of the spaces between theconductors, and again there can be insufficient spaces betweenconductors to contain ACF 226. As a result, an excessive amount of theACF can once again be squeezed out into the substantially transparentareas of the touch sensor panel.

FIG. 2 d illustrates a side view of exemplary first attachment area 204on flex circuit 200 having a third conductor configuration according toembodiments of the invention. In the example of FIG. 2 d, a particularnumber of dummy conductors 222 can be formed between active conductors220. The number of dummy conductors 222, and the spacing between thedummy conductors and active conductors 220, can be chosen (e.g.,empirically) in accordance with the type and thickness of flex circuit200 and the cross-sectional dimensions of the conductors. By the properselection of conductor spacing, enough space can remain between theconductors (dummy and active) to retain most of the ACF underneath firstattachment area 204, minimizing the amount of ACF that is squeezed out.

FIG. 3 illustrates a top and side view of a distal end of an exemplarysecond attachment area as shown in FIG. 1 b according to embodiments ofthe invention. In the example of FIG. 3, second attachment area 306 caninclude base film 310 (e.g. polyamide), upon which conductive tracelayer 312 (e.g. plated copper) and insulator 314 (a.k.a. coverlay orcover film) can be formed. Stiffener 328, which also acts as a spacer,can be attached at the distal end of second attachment area 306 toensure that sufficient bonding pressure is achieved at the distal end.

As mentioned above, conventional flex circuits having traces on bothsides require vias formed in the base film and plating to establish anelectrical connection through the via. Insulators are also required onboth sides of the flex circuit to protect the conductive traces formedthereon. Because of the dual plated traces and dual insulators, and theoverall increased thickness of conventional flex circuits, conventionaldual-sided flex circuits provide shielding for the conductive traces. Toprovide enhanced shielding for single-sided flex circuits according toembodiments of the invention, thin conductive films can be attached toboth sides of the flex circuits.

FIG. 4 a illustrates a side view of an exemplary flex circuit 400including conductive film 430 on the top side and optionally the bottomside 436 according to embodiments of the invention. Note that FIG. 4 ais not to scale, and has exaggerated dimensions for purposes ofillustration only. In the example of FIG. 4 a, flex circuit 400 caninclude base film 410, upon which a layer of conductive traces 412 (e.g.copper) and an insulator 414 can be formed. One or more of conductivetraces 412 can be held at a fixed potential (e.g. ground). In oneembodiment, first opening (or notch) 432 in insulator 414 can be formedover a particular conductive trace that is held at a fixed potentialsuch as ground. Conductive film 430 can then be applied over insulator414, where it can conform to the shape of opening 432 and makeelectrical contact with one or more of the fixed potential traces tohold the conductive film at the fixed potential. When conductive film430 is held at the fixed potential, it can serve as a shield forconductive traces 412.

In another embodiment, before any conductive film is applied, secondopening (or notch) 434 can also be formed through base film 410 andinsulator 414, while avoiding any conductive trace 412. Conductive film430 can then be applied over insulator 414, where it can conform to theshape of opening (or notch) 434 and make electrical contact with one ormore of the fixed potential traces to hold the conductive film at thefixed potential. Conductive film 436 can then be applied over base film410, where it can conform to hole 434 and make electrical contact withconductive film 414 on the opposite side. In this manner, the conductivefilm on both sides of the flex circuit can be held at a fixed potentialand serve as shields.

FIG. 4 b illustrates a top view of exemplary flex circuit 400 withopening 432 or 434 in at least insulator 414 for holding at least oneconductive film at a fixed potential according to embodiments of theinvention.

FIG. 4 c illustrates a top view of exemplary flex circuit 400 with notch432 or 434 in at least insulator 414 for holding at least one conductivefilm at a fixed potential according to embodiments of the invention.

FIG. 4 d illustrates a top view of exemplary flex circuit 400 with adifferent notch 432 or 434 in at least insulator 414 for holding atleast one conductive film at a fixed potential according to embodimentsof the invention.

FIG. 4 e illustrates a top view of exemplary flex circuit 400 with nonotch. In the embodiment of FIG. 4 e, conductive films 430 and 436extend beyond (overhang) base film 414 and are conductively bonded inthe overhanging area for holding both conductive films at a fixedpotential according to embodiments of the invention.

FIGS. 5 a and 5 b illustrate perspective views of exemplary flex circuit500 in its original flattened fabrication configuration according toembodiments of the invention. In the example of FIGS. 5 a and 5 b, flexcircuit 500 includes first attachment area 504 that include activeconductors 520 and dummy conductors 522 formed along its length. Flexcircuit 500 also includes second attachment area 506 that can includeconductors 524 formed at its distal ends. In the example of FIGS. 5 aand 5 b, flex circuit 500 is formed from base film 510, and includesconductive traces and an insulator (not shown) formed only on the sideof the base film visible in FIG. 5 b. Tail 504, which is integrallyformed as part of flex circuit 500, contain tail conductors forconnecting to connector 538.

FIG. 6 illustrates exemplary computing system 600 that can include oneor more of the embodiments of the invention described above. Computingsystem 600 can include one or more panel processors 602 and peripherals604, and panel subsystem 606. Peripherals 604 can include, but are notlimited to, random access memory (RAM) or other types of memory orstorage, watchdog timers and the like. Panel subsystem 606 can include,but is not limited to, one or more sense channels 608, channel scanlogic 610 and driver logic 614. Channel scan logic 610 can access RAM612, autonomously read data from the sense channels and provide controlfor the sense channels. In addition, channel scan logic 610 can controldriver logic 614 to generate stimulation signals 616 at variousfrequencies and phases that can be selectively applied to drive lines oftouch sensor panel 624. In some embodiments, panel subsystem 606, panelprocessor 602 and peripherals 604 can be integrated into a singleapplication specific integrated circuit (ASIC).

Touch sensor panel 624 can include a capacitive sensing medium having aplurality of drive lines and a plurality of sense lines, although othersensing media can also be used. Each intersection of drive and senselines can represent a capacitive sensing node and can be viewed aspicture element (pixel) 626, which can be particularly useful when touchsensor panel 624 is viewed as capturing an “image” of touch. (In otherwords, after panel subsystem 606 has determined whether a touch eventhas been detected at each touch sensor in the touch sensor panel, thepattern of touch sensors in the multi-touch panel at which a touch eventoccurred can be viewed as an “image” of touch (e.g. a pattern of fingerstouching the panel).) Each sense line of touch sensor panel 624 candrive sense channel 608 (also referred to herein as an event detectionand demodulation circuit) in panel subsystem 606. Touch sensor panel 624can be connected to panel subsystem 606, panel processor 602 andperipherals 604 through the flex circuit according to embodiments of theinvention.

Computing system 600 can also include host processor 628 for receivingoutputs from panel processor 602 and performing actions based on theoutputs that can include, but are not limited to, moving an object suchas a cursor or pointer, scrolling or panning, adjusting controlsettings, opening a file or document, viewing a menu, making aselection, executing instructions, operating a peripheral deviceconnected to the host device, answering a telephone call, placing atelephone call, terminating a telephone call, changing the volume oraudio settings, storing information related to telephone communicationssuch as addresses, frequently dialed numbers, received calls, missedcalls, logging onto a computer or a computer network, permittingauthorized individuals access to restricted areas of the computer orcomputer network, loading a user profile associated with a user'spreferred arrangement of the computer desktop, permitting access to webcontent, launching a particular program, encrypting or decoding amessage, and/or the like. Host processor 628 can also perform additionalfunctions that may not be related to panel processing, and can beconnected to program storage 632 and display device 630 such as an LCDdisplay for providing a UI to a user of the device. Display device 630together with touch sensor panel 624, when located partially or entirelyunder the touch sensor panel, can form touch screen 618.

Note that one or more of the functions described above can be performedby firmware stored in memory (e.g. one of the peripherals 604 in FIG. 6)and executed by panel processor 602, or stored in program storage 632and executed by host processor 628. The firmware can also be storedand/or transported within any computer-readable medium for use by or inconnection with an instruction execution system, apparatus, or device,such as a computer-based system, processor-containing system, or othersystem that can fetch the instructions from the instruction executionsystem, apparatus, or device and execute the instructions. In thecontext of this document, a “computer-readable medium” can be any mediumthat can contain or store the program for use by or in connection withthe instruction execution system, apparatus, or device. The computerreadable medium can include, but is not limited to, an electronic,magnetic, optical, electromagnetic, infrared, or semiconductor system,apparatus or device, a portable computer diskette (magnetic), a randomaccess memory (RAM) (magnetic), a read-only memory (ROM) (magnetic), anerasable programmable read-only memory (EPROM) (magnetic), a portableoptical disc such a CD, CD-R, CD-RW, DVD, DVD-R, or DVD-RW, or flashmemory such as compact flash cards, secured digital cards, USB memorydevices, memory sticks, and the like.

The firmware can also be propagated within any transport medium for useby or in connection with an instruction execution system, apparatus, ordevice, such as a computer-based system, processor-containing system, orother system that can fetch the instructions from the instructionexecution system, apparatus, or device and execute the instructions. Inthe context of this document, a “transport medium” can be any mediumthat can communicate, propagate or transport the program for use by orin connection with the instruction execution system, apparatus, ordevice. The transport readable medium can include, but is not limitedto, an electronic, magnetic, optical, electromagnetic or infrared wiredor wireless propagation medium.

FIG. 7 a illustrates exemplary mobile telephone 736 that can includetouch sensor panel 724 and display device 730, the touch sensor panelconnected to a panel subsystem using the flex circuit according toembodiments of the invention.

FIG. 7 b illustrates exemplary digital media player 740 that can includetouch sensor panel 724 and display device 730, the touch sensor panelconnected to a panel subsystem using the flex circuit according toembodiments of the invention. The mobile telephone and media player ofFIGS. 7 a and 7 b can maintain a smaller, lower cost physical product byutilizing the flex circuit according to embodiments of the invention.

Although embodiments of this invention have been fully described withreference to the accompanying drawings, it is to be noted that variouschanges and modifications will become apparent to those skilled in theart. Such changes and modifications are to be understood as beingincluded within the scope of embodiments of this invention as defined bythe appended claims.

What is claimed is:
 1. A method for providing electrical connections toboth sides of a touch sensor panel, comprising: forming conductivetraces on a first surface of a base film; shaping the base film to formfirst and second attachment areas, the first and second attachment areasincluding the conductive traces; forming a conductive shield over theconductive traces, the shield electrically coupled to one or more of theconductive traces; and folding the base film such that the conductivetraces on the first and second attachment areas are positioned andaligned for attachment to pads on first and second sides of the touchsensor panel.
 2. The method of claim 1, further comprising forming aninsulator between the conductive shield and the conductive traces. 3.The method of claim 1, further comprising forming active and dummyconductors on the first attachment area and lower conductors on thesecond attachment area, the lower conductors arranged in conjunctionwith the active and dummy conductors so that when the flex circuit isfolded and attached to the touch sensor panel, the lower conductors andthe active and dummy conductors are not on directly opposing sides ofthe touch sensor panel.
 4. The method of claim 1, further comprisingintegrally forming a tail with the flex circuit, the tail containingtail conductors for connecting to a logic board.
 5. The method of claim1, further comprising: forming active and dummy conductors on the firstattachment area, with one or more dummy conductors placed between eachactive conductor; and spacing the active and dummy conductors tosubstantially contain conductive bonding material used to bond the firstattachment area to the touch sensor panel.
 6. The method of claim 2,further comprising: forming lower conductors on the second attachmentarea; limiting the insulator to expose the lower conductors at eachdistal end of the second attachment area; and adding a stiffener at eachdistal end of the second attachment area, the stiffeners and the exposedlower conductors located on directly opposing sides of the distal endsof the second attachment area.
 7. The method of claim 2, wherein formingthe conductive shield comprises: forming a first conductive film overthe insulator; and connecting the first conductive film to one or moreof the conductive traces for holding the first conductive film at afixed potential.
 8. The method of claim 7, further comprising forming afirst opening in the insulator for providing a connection from the firstconductive film to the one or more conductive traces.
 9. The method ofclaim 8, further comprising: forming a second conductive film on asecond surface of the base film; and connecting the second conductivefilm to one or more of the conductive traces for holding the secondconductive film at a fixed potential.
 10. The method of claim 9, furthercomprising forming a second opening in the base film and the insulatorfor providing a connection from the second conductive film to the firstconductive film.
 11. The method of claim 10, wherein either or both ofthe first and second openings are notches.
 12. The method of claim 8,further comprising: forming a bottom conductive film on a bottom side ofthe flex circuit; overhanging the top and bottom conductive films beyondthe flex circuit; and conductively bonding the top and bottom conductivefilms in the overhanging area.